"Blocked Plugin" is a tough one. Usually it can't be gotten around because Apple doesn't allow "downgrading" plugins.
These steps have worked in a very limited few cases.
Download the offline installer: Flash Player (Mac OS X)
Download the Shockwave FULL Installer here: http://get.adobe.com/shockwave/otherversions/
Save the files - DON'T run them yet.
Go to: Mac HD/Library/Internet Plugins
Trash the Flash Player.plugin file and the flashplayer.xpt file from there.
Go to: Mac HD/Library/PreferencePanes
Trash the Flash Player.prefPane from there.
Go to: Mac HD/Library/Application Support/Adobe
Trash the Flash Player Install Manager folder and Shockwave 12 folder (if it's there)
Also in Mac HD/Library/Application Support/Adobe, trash the Macromedia folder (if it's there)
Go to: [user]/Library/Preferences
Trash the Macromedia folder
Empty the trash.
Making sure your browser is fully quit, run the Flash Player Installer and the Shockwave Installer.
Open Safari and go to Safari>Preferences
Under the Security tab, Make sure "Allow all other plugins" is checked.
Hopefully, that will do it.